If you believe that Harper has peaked, then no way he makes the Hall. If you believe he is just entering his prime, then he has a decent chance.
If you look at HOF standards in RF, it’s not too optimistic though.
https://www.baseball-reference.com/leaders/jaws_RF.shtmlI think the counting stats won’t matter much. If Bryce plays out that contract he will be on the ballot in 2036 at the earliest. The entire HOF electoral will have turned over and be almost entirely made up of those with a sabermetric bent.
I personally am of the mind that Harper has already peaked. I don’t think the Nats just let him walk if they genuinely thought the next six years would be better than the last six. That combined with effect on clubhouse chemistry and I understand giving him a token offer and letting him walk.